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Hailong Dao
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I am not sure I understand the analogue correctly, but in the commutative case, one can get to depth zero with 3 generators. That is because any second syzygy module is isomorphic to a second syzygy of a 3-generated ideal. It is explained here:

http://www.math.uiuc.edu/Macaulay2/doc/Macaulay2-1.2/share/doc/Macaulay2/Bruns/html/

You can take the N to be second syzygy of $m=(t,y_1,...,y_n)$, so $N$ has depth 3. Produce a three generated ideal $I$ such that $syz^2(I)\cong N$. So $depth I =3-2=1$, and $depth R/I=0$.

I think Theorem 13.4 shows that $dim R/I=0$ implies $I$ is at least $n+1$-generated.

Hailong Dao
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